Ships worsen air pollution

A SHIPPING boom is aggravating air pollution in China and other nations in east Asia (東亞), and according to scientists causing thousands of deaths a year in a region with eight of the world’s 10 biggest container ports.

Often overlooked compared to cars and factories that are far bigger causes of smog, marine traffic has more than doubled off east Asia since 2005 and some pollution from the fuel oil of ships wafts inland, they said.

The Chinese-led study estimated that sulphur dioxide, which generates acid rain, and other pollution from ships caused an estimated 24,000 premature deaths a year in the region, mainly from heart and lung diseases, and cancer.

About three-quarters of the deaths were in mainland China, and others in Japan, Taiwan, Hong Kong, Macau and South Korea, according to the study published in the journal Nature Climate Change (自然氣候變) based on satellite data tracking almost 19,000 vessels.

The death toll is a tiny though rising share of an estimated one million deaths caused annually by air pollution in the region, the study found. Given many uncertainties, the number of deaths could be as low as 14,500 or as high as 37,500, it said.

“A few years ago in east Asia the levels of shipping just weren’t that large. Now they’re huge,” said Drew Shindell, one of the authors of the report.

The study also found that emissions of carbon dioxide, the main man-made greenhouse gas, from shipping off east Asia had doubled in less than a decade to 16 percent of the global total from the industry in 2013.

Other air pollutants from ships have a cooling effect on global climate, however, by reflecting sunlight into space.

(This article is published on Sing Tao Daily on 26 July 2016)


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